class_docstr: Batch optimizer.
  
  Attributes
  ----------
  value: float
  allowed_set: float
code: def __init__(self, value, allowed_set=None):
      self._value = value
      if allowed_set is None:
          self._allowed_set = [value]
      else:
          if len(allowed_set) > len(set(allowed_set)):
              raise ValueError("values in allowed_set must be unique.")
          self._allowed_set = allowed_set
  
label_desc: Use image node_id 1 to create a new Batch object  with example: obj = Batch(value, allowed_set)